Light emitting device with optical enhancement structure

Abstract

A light emitting device with optical enhancement structure. The light emitting device includes a light emitting element and an optical enhancement structure. Some of the light from the light emitting element is emitted in a diverging manner. The optical enhancement structure is optically coupled to the light emitting element, said optical enhancement structure having a light emerging surface that includes a central surface that is orthogonal to the normal and corner surfaces having profiles that are not orthogonal to the normal. The optical enhancement structure is a single structure for changing the normal angle of the first light emerging surface to increase light output efficiency.

1 . A light emitting device having a plurality of pixels, each pixel defined by a structure comprising: 
 a light emitting element, wherein some of the light from the light emitting element is emitted in a diverging manner; and    an optical enhancement structure that is optically coupled to the light emitting element, said optical enhancement structure having a light emerging surface that includes a central surface that is orthogonal to the normal and corner surfaces having profiles that are not orthogonal to the normal.    
   
   
       2 . The light emitting device as in  claim 1 , wherein the light emerging surface having a surface profile that reduces total internal reflection at the light emerging surface.  
   
   
       3 . The light emitting device as in  claim 1 , wherein the corner surface profiles comprise at least one of: 
 an arcuate profile,    a faceted profile, and    a beveled profile.    
   
   
       4 . The light emitting device as in  claim 3 , wherein the surface profile comprises a convex light emerging surface.  
   
   
       5 . The light emitting device as in  claim 4 , wherein the convex light emerging surface comprises an arcuate profile extending across the light emerging surface.  
   
   
       6 . The light emitting device as in  claim 5 , wherein the optical enhancement structure directs diverging light from the light emitting element along a path within the optical enhancement structure in a direction towards a normal of the pixel.  
   
   
       7 . The light emitting device as in  claim 6 , wherein the optical enhancement structure bends diverging light from the light emitting element to transmit along a path within the optical enhancement structure towards closer to the normal.  
   
   
       8 . The light emitting device as in  claim 7 , further comprising a passivation layer between the light emitting element and the optical enhancement structure, wherein the refractive index of the optical enhancement structure is higher than the refractive index of the optical enhancement structure.  
   
   
       9 . The light emitting device as in  claim 1 , wherein the optical enhancement structure comprises at least two adjacent optical elements having an interfacing surface between the adjacent optical elements, wherein the interfacing surface is shaped to reduce total internal reflection at the interfacing surface.  
   
   
       10 . The light emitting device as in  claim 9 , wherein the interfacing surface includes a central surface that is orthogonal to the normal and corner surfaces having profiles that are not orthogonal to the normal.  
   
   
       11 . The light emitting device as in  claim 10 , wherein the corner surface profiles comprise at least one of: 
 an arcuate profile,    a faceted profile, and    a beveled profile.    
   
   
       12 . The light emitting device as in  claim 11 , wherein the interfacing surface comprises a convex surface.  
   
   
       13 . The light emitting device as in  claim 12 , wherein the convex surface comprises an arcuate profile extending across the light emerging surface.  
   
   
       14 . The light emitting device as in  claim 13 , wherein one of the optical elements comprises a substantially flat light emerging surface.  
   
   
       15 . The light emitting device as in  claim 14 , wherein the optical elements have different refractive indices.  
   
   
       16 . The light emitting device as in  claim 15 , wherein the optical element closer to the light emitting element has a higher refractive index than the optical element further from the light emitting element.  
   
   
       17 . The light emitting device as in  claim 16 , further comprising a passivation layer disposed between the optical enhancement structure and the light emitting element, wherein the refractive index of the passivation layer is higher than the refractive indices of the optical elements.  
   
   
       18 . The light emitting device as in  claim 1 , wherein the light emitting element is one of OLED, PLED and plasma panel display.  
   
   
       19 . A display device, comprising: 
 a light emitting device as in  claim 1;  and    a controller operatively controlling the light emitting element of each pixel.    
   
   
       20 . An electronic device, comprising: 
 the display device as in  claim 19;  and    a control device operatively controlling the operation of the display device to display an image in accordance with image data.    
   
   
       21 . A method of enhancing light output from a light emitting element of a pixel in a light emitting device, comprising the steps of: 
 providing an optical enhancement structure that has an optical characteristic that refracts incident light to transmit along a path within the optical enhancement structure towards a normal of the structure; and    optically coupling the optical enhancement structure to the light emitting element to direct diverging light from the light emitting element along a path within the optical enhancement structure towards a normal of the pixel.